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Texaskev
10-20-2011, 11:24 AM
I have 2 sets of Atc 200 forks that are bent. One is an 81 which is year specific. The other is 82. Anybody got any ideas to straighten? I have a 12 ton press, but it is not large enough to put them into to work. Tried a couple of different things that wouldn't do it.........Next is to try to heat and bend....Any other ideas? I hate to scrap these old parts............Keep in mind these are one piece no suspension.
Thanks

fabiodriven
10-20-2011, 11:37 AM
Chain it to a tree and pull it with a car. No joke.

El Camexican
10-20-2011, 12:00 PM
As long as they are not so bad that they are kinked, or binding I just turn them 180 degrees in the tree and hope that some day I'll hit whatever it was that tweeked them the first time. DO NOT HEAT THEM

250rRoostmaster
10-20-2011, 12:17 PM
Chain it to a tree and pull it with a car. No joke.

Have you used this technique personally? Sounds crazy but i've heard crazier!!!!

fabiodriven
10-20-2011, 12:25 PM
Many years ago yes, I did do it. It works.

El Camexican
10-20-2011, 12:33 PM
I've seen guys turn them 180 degrees in the tree and drive them up against a garage wall and blip the gas until they straighten. I'm sure it helped put flat spots on those old ball bearing style steering-head bearings at the same time.

Texaskev
10-20-2011, 03:09 PM
Fabio-I tried the tree and come-a-long technique, no dice. They are off the bike now.
El Camexican- These are 1 piece forks, you can't turn them 180. Why not heat them? I can re heat treat them.....I have the technology......These forks are pretty damn tough!

fabiodriven
10-20-2011, 03:20 PM
I didn't say come-along, I said car. You need the shock load of something big.

One time a bought a little Subaru that had been smashed. I was going to fix it to use as my daily driver. It didn't really have a frame, but the sub-frame in the front was crinkled in. I needed to pull it out or there was no way the front bumper would go on straight. I tied the back of the car to a tree and hooked up a chain-fall to the front. The car kept doing all sorts of twisting and sliding around, but the crinkle just wouldn't come out. Finally I said fack this and I untied the car from the tree. I hooked a chain to the frame and then to the back of my F-350. After about 5 good hard tugs the frame was right back where it was supposed to be.

It was an impact that got it bent in the first place, and an impact brought it back to where it needed to be.

Texaskev
10-20-2011, 03:38 PM
Fabio- This is playing over in my mind...........and the visual is funny as SH**! I'm going to try 1 or 2 more things, and then what the hell.........My only problem is the ol' 200 is stripped down for repaint and such. It might be a little while before I can try the old truck yankin'..............but it will probably be fun! I will have to have an ice chest full of beer for this one, and that's right up my alley...............Neighbors ought to enjoy it too!

El Camexican
10-20-2011, 03:40 PM
El Camexican- These are 1 piece forks, you can't turn them 180. Why not heat them? I can re heat treat them.....I have the technology......These forks are pretty damn tough!

Sorry, did not catch that. I thought you were talking about chrome shafts. You can heat your type if that's the way you want to go. If the fork is round and not kinked you can head the front side with a torch and when you have a red spot th esize of a quarter place a soaking wet rag on it and keep it there until the fork cools down enough to "shrink" back into shape. Don't get burnt by hot steam. If you know a guy that builds hand rails for a living invite him over for a beer when you are about to do this.

Texaskev
10-20-2011, 03:47 PM
Sorry, did not catch that. I thought you were talking about chrome shafts. You can heat your type if that's the way you want to go. If the fork is round and not kinked you can head the front side with a torch and when you have a red spot th esize of a quarter place a soaking wet rag on it and keep it there until the fork cools down enough to "shrink" back into shape. Don't get burnt by hot steam. If you know a guy that builds hand rails for a living invite him over for a beer when you are about to do this.


Yeah I've done some shrinking like that. Kind of what I had in mind....to tell the truth. One set is not bent badly. The other is bent pretty good, but no kinks......maybe I will document this and do a "tips" thread. I could just put a set off of a 200s on it, or another original set, but what fun is that?

El Camexican
10-20-2011, 04:55 PM
I could just put a set off of a 200s on it, or another original set, but what fun is that?

Exactly, no hammers+no sparks+no blood = no fun

Texaskev
10-31-2011, 03:17 PM
Ok, a little follow up. I locked the forks down, and heated the back side with a torch. About the size of a quarter....five foot long section of square tubing, pulled it back to straight, one leg at a time. Since I heated the back side, all was bent in tension. This meant no wrinkling or collapsing. Took my time and got it right. Afterwards, re-heated the areas, and quenched in oil. After beadblasting the area, no deformation exists. These forks had to be bent back about 2 inches at the axle. The bent area was at the lower side of the factory brace. All in all took me about 20 minutes. The next set is bent back about 6 inches at the axle, with almost a small flat area just below the brace. We shall see how the second set turns out.........Fabio, wish I could've tried the truck yankin' (kindof) but maybe the second set will need it! LOL

El Camexican
11-02-2011, 12:51 AM
Glad to hear it worked out.